Ad Widget


Triggers expressions with Item Thresholds

  • Filter
  • Time
  • Show
Clear All
new posts

    Triggers expressions with Item Thresholds

    There are 2 items in the template named Return Air Temp and Return Air Temp Threshold. Both of these items are polled by snmp, the Return air temp every 10s and the Threshold every 1d. The threshold will never change since that is a value we already set on the units themselves. It is set to 104F. Right now our Return Air temp is at 76F.

    I want to create a trigger called Return Temp Warning. If the value of item Return Air Temp exceeds the value of Return Air Temp Threshold for 3m then throw warning. And another one called Critical if the same conditions apply but for more then 10m.

    I have looked through the expression creator and didn't see any way to have the expression use another item to check for a condition. Also on another note, If I am using a pre-processing expression to provide the correct values for the Items data will that effect the expression for the trigger. What I mean is that the raw data from the OID for Return Air Temp is 760. I use pre-processing and the expression "scale" by 0.1, to adjust the readout and storage of the data to 76.0.

    Now if I have to manually set a value in the triggers expression should I use value that is true to the raw data or the data after pre-processing.
    Last edited by PedroKhan; 14-08-2019, 22:50.

    If the value never changes wouldn't be better to use a MACRO?
    Have you tried something like?
    {template:air_temp.count( 300, $TEMPERATURE_LIMIT, gt )}>=30
    This count function will return the number of values read on the last 300 seconds that are greater than (gt) $TEMPERATURE_LIMIT (If you don't want to use macros just replace it with the other item), since you are reading the item in 10s intervals you will have 30 if all of them are greater than $TEMPERATURE_LIMIT
    Probably you would prefer to use some tuning and maybe there are better ways, but i think this can solve your problem.
    Check the trigger functions on the documentation: